A locomotive spring automatic design method and system

Abstract

The present invention provides a method and system for automatic design of locomotive springs. The method of the present invention comprises the following steps: obtaining information on locomotive axle weight, number of locomotive axles, bogie weight, unsprung weight, and static deflection of springs; calculating the load of each group of springs respectively; inputting feasible values ​​of spring mean diameter, spring wire diameter, and working height, wherein the feasible values ​​are within a feasible range; performing verification calculations based on the input feasible values, and outputting the feasible values ​​when the constraint conditions are met, wherein the verification calculations include shear stress verification, clearance verification under maximum load, spring fatigue verification, and spring stability verification. The present invention is easy to operate and intuitive, effectively avoids errors in traditional calculations, greatly improves design efficiency, and avoids problems such as complicated parameters, easy errors, time-consuming and labor-intensiveness in the design process of locomotive springs. It has functions such as alarm prompts when the calculated parameters exceed the empirical values. The boundary interval values ​​are set according to design experience to improve the efficiency of optimized design.

Description

Technical Field

[0001] The present invention relates to the technical field of locomotive spring design, and in particular to a locomotive spring automatic design method and system. Background Art

[0002] Locomotive springs are key components used in locomotive suspension systems. With the advancement of production and science and technology, locomotives are developing towards high speed and heavy load. Locomotive spring design parameters are complicated, and design calculations are affected by many factors and parameters. Mistakes can easily occur if you are not careful, and it takes a lot of energy and time, which creates a lot of resistance to quickly formulating solutions and cannot improve design efficiency.

[0003] At present, there are many spring design software on the market. These software are obtained by listing relevant formulas according to spring design or calculation standards. They are general software with high purchase cost, poor adaptability on locomotives, cumbersome operation, and many functions cannot be used. The cost performance is low for locomotive spring design. In summary, the existing technology has the following disadvantages: 1) High purchase cost. 2) Many functions cannot be used, poor usability in locomotive spring design, and cumbersome operation. 3) There are no design experience values ​​and parameter range prompts for relevant parameters. 4) The professional quality requirements for spring design engineers are high. Therefore, it is very necessary to compile and develop a special software for locomotive spring design. Summary of the invention

[0004] According to the technical problems raised above, a method and system for automatic design of locomotive springs are provided. The present invention is compiled by using Visual Basic programming software. According to the design experience of locomotive spring design, the range values ​​of relevant parameters are set. The software can automatically formulate the design scheme of the spring and has an alarm prompt function, which provides a convenient and quick method for the design of locomotive springs. The technical means adopted by the present invention are as follows:

[0005] A locomotive spring automatic design method comprises the following steps:

[0006] Step 1, obtaining locomotive axle weight, locomotive axle number, bogie weight, unsprung weight, primary spring static deflection and secondary spring static deflection information;

[0007] Step 2: Based on the information obtained in step 1, calculate the load of each group of springs in the first series and the second series respectively;

[0008] Step 3, input feasible values ​​of the spring center diameter D, spring wire diameter d, and working height H of the first series and second series springs, wherein the feasible values ​​are within the feasible range;

[0009] Step 4: Perform verification calculation based on the input feasible value, output the feasible value when the constraint condition is met, and return to step 3 when the constraint condition is not met, wherein the verification calculation includes shear stress verification, clearance verification under maximum load, spring fatigue verification and spring stability verification.

[0010] Furthermore, in step 2,

[0011] The first series uses a coil spring, and the load is calculated as follows: P1 = (G0-G2) g / 4,

[0012] Wherein, G1 is the obtained bogie weight, in t; G2 is the obtained unsprung weight, in t, and g is the gravitational acceleration;

[0013] The number of single-group secondary springs: m2, value 2 or 3;

[0014] The load of a single secondary spring is P2 = (n0*G0-m*G1)g / 2m*m2;

[0015] Among them, n0 is the number of locomotive axles obtained, which can be 4 or 6; G0 is the axle weight of the locomotive obtained, in t; m is the number of bogies obtained, which can be 2 or 3.

[0016] Furthermore, in step 3, the feasible range is specifically:

[0017] The diameter range of primary spring wire is: 20, 22, 24, 34.75, 42, 42.5, 44, 45, unit: mm;

[0018] The range of the middle diameter of the primary spring is 200 to -250 mm, and the value in the calculation increases by +2.5 mm.

[0019] The diameter range of the secondary spring is: 50.6, 52, 54, 55.8, 56.5, 60.5;

[0020] Middle diameter of secondary spring: 240~275mm, the value in calculation increases by 2.5mm;

[0021] The first series working height H1 has a setting range of 150mm to -300mm, and the value in the calculation increases by a step of +5mm;

[0022] The second system working height H2 has a setting range of 450mm to -600mm, and the values ​​taken in the calculation increase in steps of +5mm.

[0023] Furthermore, in step 4, the checking constraint condition includes: the convolution ratio C=D / d≥4.

[0024] Furthermore, in step 4, the shear stress check is specifically as follows:

[0025]

[0026] The allowable shear stress [t] is a constant, and a is a correction factor, which satisfies

[0027] Furthermore, the clearance check under the maximum load is specifically as follows:

[0028] Q=[(H0-1.4fd) / n]-d; Q≤0.1d;

[0029] Among them, the vertical stop position of the spring is set to a maximum dynamic load coefficient of 0.4 according to the locomotive operation experience. At this time, the deflection is 1.4f, where f is the static deflection. According to the spring deflection formula Calculate, where G is the shear modulus, which is a constant, and n is the number of effective coils of the spring, which satisfies

[0030] The total number of spring turns N = n + 1.5;

[0031] Spring free height H0 = H + f.

[0032] Furthermore, in step 4, the spring fatigue check is specifically as follows:

[0033] Calculation of extreme values ​​of dynamic load: P max =(1+μ)P, minimum dynamic load P min =(1-μ)P;

[0034] Among them, μ is the dynamic load coefficient; the design experience value μ=0.3 is selected.

[0035] Calculation of shear stress during dynamic load:

[0036] Maximum shear stress under dynamic load t max =8aDP max / (πd 3 )≤[t];

[0037] Minimum shear stress under dynamic load t min =8aDP min / (πd 3 )≤[t];

[0038] Pulse fatigue limit stress calculation: t uo =0.32R m , where the tensile strength R m is a constant, depending on the spring steel material;

[0039] Fatigue safety factor calculation: S = (t uo +0.75t min ) / tmax ≥S min

[0040] Among them, S min As the minimum safety factor, the design experience value of 1.3 is selected.

[0041] Furthermore, the spring stability check includes: locomotive spring height-to-diameter ratio λ=H0 / D≤3, wherein H0 is the free height of the spring.

[0042] The present invention also discloses a locomotive spring automatic design system, comprising:

[0043] A locomotive spring data acquisition unit, used to acquire information on locomotive axle weight, number of locomotive axles, bogie weight, unsprung weight, primary spring static deflection, and secondary spring static deflection;

[0044] A locomotive spring data calculation unit, used to calculate the load of each group of springs of the first series and the second series according to the data obtained by the locomotive spring data acquisition unit;

[0045] The locomotive spring data selection unit is used to input feasible primary and secondary spring data, including spring center diameter D, spring wire diameter d, and working height H;

[0046] The locomotive spring verification unit is used to perform verification calculations based on the numerical values ​​provided by the locomotive spring data selection unit, output the feasible value when the constraint conditions are met, and issue an alarm prompt when the constraint conditions are not met.

[0047] The invention is easy to operate and intuitive, effectively avoids the errors of traditional calculations, greatly improves the design efficiency, and avoids the problems of complicated parameters, easy errors, time-consuming and labor-intensive in the design process of locomotive springs. It has functions such as alarm prompts when the calculated parameters exceed the empirical values. The boundary interval value is set according to the design experience to improve the optimization design efficiency.

[0048] The prompt includes that a specific feasible data parameter is out of range.

[0049] For primary spring calculation, when D, d, and H overflow, an alarm is issued and H, D, and d values ​​outside the range are automatically selected for calculation;

[0050] For the calculation of secondary springs, when D, d, and H overflow, m2=3 is assigned, and H, D, and d values ​​within the range are automatically selected for calculation; when D, d, and H overflow and m2=3, an alarm is issued and H, D, and d values ​​outside the range are automatically selected for calculation. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0052] Figure 1 It is a flow chart of the present invention. DETAILED DESCRIPTION

[0053] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0054] like Figure 1 As shown, the embodiment of the present invention discloses a method for automatically designing a locomotive spring, comprising the following steps:

[0055] Step 1, obtaining locomotive axle weight, locomotive axle number, bogie weight, unsprung weight, primary spring static deflection and secondary spring static deflection information;

[0056] Step 2: Based on the information obtained in step 1, calculate the load of each group of springs in the first series and the second series respectively;

[0057] Step 3, input feasible values ​​of the spring center diameter D, spring wire diameter d, and working height H of the first series and second series springs, wherein the feasible values ​​are within the feasible range;

[0058] Step 4: Perform verification calculation based on the input feasible value, output the feasible value when the constraint condition is met, and return to step 3 when the constraint condition is not met, wherein the verification calculation includes shear stress verification, clearance verification under maximum load, spring fatigue verification and spring stability verification.

[0059] In the step 2,

[0060] The first series uses a coil spring, and the load is calculated as follows: P1 = (G0-G2) g / 4,

[0061] Wherein, G1 is the obtained bogie weight, in t; G2 is the obtained unsprung weight, in t, and g is the gravitational acceleration;

[0062] The number of single-group secondary springs: m2, value 2 or 3;

[0063] The load of a single secondary spring is P2 = (n0*G0-m*G1)g / 2m*m2;

[0064] Among them, n0 is the number of locomotive axles obtained, which can be 4 or 6; G0 is the axle weight of the locomotive obtained, in t; m is the number of bogies obtained, which can be 2 or 3.

[0065] In step 3, the feasible range is specifically:

[0066] The diameter range of primary spring wire is: 20, 22, 24, 34.75, 42, 42.5, 44, 45, unit: mm;

[0067] The range of the middle diameter of the primary spring is 200 to -250 mm, and the value in the calculation increases by +2.5 mm.

[0068] The diameter range of the secondary spring is: 50.6, 52, 54, 55.8, 56.5, 60.5;

[0069] Middle diameter of secondary spring: 240~275mm, the value in calculation increases by 2.5mm;

[0070] The first series working height H1 has a setting range of 150mm to -300mm, and the value in the calculation increases by a step of +5mm;

[0071] The second system working height H2 has a setting range of 450mm to -600mm, and the values ​​taken in the calculation increase in steps of +5mm.

[0072] In step 4, the checking constraint conditions include: the convolution ratio C=D / d≥4.

[0073] In step 4, the shear stress under static load is less than the allowable shear stress [t] of the material, and the shear stress check is specifically as follows:

[0074]

[0075] The allowable shear stress [t] is a constant, and a is a correction factor, which satisfies Wherein P includes P1 and P2.

[0076] The clearance check under the maximum load is specifically as follows:

[0077] Q=[(H0-1.4fd) / n]-d; Q≤0.1d; t≤[t];

[0078] Among them, the vertical stop position of the spring is set to a maximum dynamic load coefficient of 0.4 according to the locomotive operation experience, then the deflection is 1.4f, f is the static deflection, which includes the static deflection of the primary spring: f1, unit mm; the static deflection of the secondary spring: f2, unit mm; According to the spring deflection formula Calculate, where G is the shear modulus, which is a constant, and n is the number of effective coils of the spring, which satisfies

[0079] The total number of spring turns N = n + 1.5;

[0080] Spring free height H0 = H + f.

[0081] In step 4, the spring fatigue check is specifically as follows:

[0082] Calculation of extreme values ​​of dynamic load: P max =(1+μ)P, minimum dynamic load P min =(1-μ)P;

[0083] Wherein, μ is the dynamic load coefficient. In this embodiment, μ is set to 0.3;

[0084] Calculation of shear stress during dynamic load:

[0085] Maximum shear stress under dynamic load t max =8aDP max / (πd 3 )≤[t];

[0086] Minimum shear stress under dynamic load t min =8aDP min / (πd 3 )≤[t];

[0087] Pulse fatigue limit stress calculation: t uo =0.32R m , where the tensile strength R m is a constant, depending on the spring steel material;

[0088] Fatigue safety factor calculation: S = (t uo +0.75t min ) / t max ≥S min

[0089] Among them, S min is the minimum safety factor.

[0090] The spring stability check includes: locomotive spring height-to-diameter ratio λ=H0 / D≤3, wherein H0 is the free height of the spring.

[0091] Spring parameter scheme verification: whether the spring wire diameter d, spring center diameter D, and working H meet the constraint conditions. When the constraint conditions are met, the output spring stiffness K=P / f, spring wire diameter d, center diameter D, working height H, free height H0, effective number of turns n, total number of turns N, shear stress t under static load, etc.

[0092] The present invention also discloses a locomotive spring automatic design system, comprising:

[0093] A locomotive spring data acquisition unit is used to acquire information on locomotive axle weight, number of locomotive axles, bogie weight, unsprung weight, primary spring static deflection, and secondary spring static deflection;

[0094] A locomotive spring data calculation unit, used to calculate the load of each group of springs of the first series and the second series according to the data obtained by the locomotive spring data acquisition unit;

[0095] The locomotive spring data selection unit is used to input feasible primary and secondary spring data, including spring center diameter D, spring wire diameter d, and working height H;

[0096] The locomotive spring verification unit is used to perform verification calculations based on the numerical values ​​provided by the locomotive spring data selection unit, output the feasible value when the constraint conditions are met, and issue an alarm prompt when the constraint conditions are not met.

[0097] The prompt includes that a specific feasible data parameter is out of range.

[0098] For primary spring calculation, when D, d, and H overflow, an alarm is issued and H, D, and d values ​​outside the range are automatically selected for calculation;

[0099] For the calculation of secondary springs, when D, d, and H overflow, m2=3 is assigned, and H, D, and d values ​​within the range are automatically selected for calculation; when D, d, and H overflow and m2=3, an alarm is issued and H, D, and d values ​​outside the range are automatically selected for calculation.

[0100] Example 1

[0101] In order to facilitate more intelligent automatic design, in this embodiment, the data D, d, and H input in step 3 are pre-set in the program, and these parameters are selected based on empirical values;

[0102] The calculation software of this embodiment is compiled by Visual Basic programming software. According to the design experience of locomotive spring design, the range values ​​of relevant parameters are set. The software can automatically formulate the design scheme of the spring and has an alarm prompt function, which provides a convenient and quick method for the design of locomotive springs. This calculation applies the idea of ​​mechanical optimization design, takes the locomotive axle weight, unsprung mass, spring working static deflection, etc. as known input quantities, takes the spring wire diameter d, spring middle diameter D and working height H as optimization target parameters, and takes shear stress, the gap between spring wires during operation, fatigue strength, and spring stability verification as constraint conditions to realize the automatic design function of locomotive springs. (Among them, the optimization targets: spring wire diameter d, spring middle diameter D and working height H, the boundary interval values ​​are set according to design experience to improve the optimization design efficiency.) The calculation software includes a design interface, background calculation, display interface and alarm prompt interface. The calculation content includes the automatic formulation function of the locomotive spring scheme, the calculation of locomotive spring load distribution, the calculation of geometric dimensions, the calculation of locomotive spring shear stress and fatigue strength, the stability verification and other calculations. After the inspection is qualified, the software interface outputs the spring parameters to complete the relevant design of the locomotive spring.

[0103] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for automatic design of locomotive springs, characterized in that: The steps include: Step 1, obtaining locomotive axle weight, locomotive axle number, bogie weight, unsprung weight, primary spring static deflection and secondary spring static deflection information; Step 2: Based on the information obtained in step 1, calculate the load of each group of springs in the first series and the second series respectively; Step 3, input feasible values ​​of the spring center diameter D, spring wire diameter d, and working height H of the first series and second series springs, wherein the feasible values ​​are within the feasible range; Step 4: Perform verification calculation based on the input feasible value, output the feasible value when the constraint condition is met, and return to step 3 when the constraint condition is not met, wherein the verification calculation includes shear stress verification, clearance verification under maximum load, spring fatigue verification and spring stability verification; In the step 2, The first series uses a coil spring, and the load is calculated as follows: P1 = (G0-G2) g / 4, Wherein, G1 is the obtained bogie weight, in t; G2 is the obtained unsprung weight, in t, and g is the gravitational acceleration; The number of single-group secondary springs: m2, value 2 or 3; The load of a single secondary spring is P2 = (n0*G0-m*G1)g / 2m*m2; Among them, n0 is the number of locomotive axles obtained, which can be 4 or 6; G0 is the axle weight of the locomotive obtained, in t; m is the number of bogies obtained, which can be 2 or 3; In step 3, the feasible range is specifically: The diameter range of primary spring wire is: 20, 22, 24, 34.75, 42, 42.5, 44, 45, unit: mm; The range of the middle diameter of the primary spring is 200 to -250 mm, and the value in the calculation increases by +2.5 mm. The diameter range of the secondary spring is: 50.6, 52, 54, 55.8, 56.5, 60.5; Middle diameter of secondary spring: 240~275mm, the value in calculation increases by 2.5mm; The first series working height H1 has a setting range of 150mm to -300mm, and the value in the calculation increases by a step of +5mm; The second system working height H2 has a setting range of 450mm to -600mm, and the values ​​taken in the calculation increase in steps of +5mm.

2. The automatic design method for motorcycle springs according to claim 1, characterized in that: In step 4, the checking constraint conditions include: the convolution ratio C=D / d≥4.

3. The automatic design method for motorcycle springs according to claim 2, characterized in that: In step 4, the shear stress check is specifically as follows: The allowable shear stress [t] is a constant, and a is a correction factor, which satisfies 4. The automatic design method for motorcycle springs according to claim 1, characterized in that: The clearance check under the maximum load is specifically as follows: Q=[(H0-1.4fd) / n]-d; Q≤0.1d; Among them, the vertical stop position of the spring is set to a maximum dynamic load coefficient of 0.4 according to the locomotive operation experience. At this time, the deflection is 1.4f, where f is the static deflection. According to the spring deflection formula Calculate, where G is the shear modulus, which is a constant, and n is the number of effective coils of the spring, which satisfies The total number of spring turns N = n + 1.5; Spring free height H0 = H + f.

5. The automatic design method for motorcycle springs according to claim 1, characterized in that: In step 4, the spring fatigue check is specifically as follows: Calculation of extreme values ​​of dynamic load: P max =(1+μ)P, minimum dynamic load P min =(1-μ)P; Where, μ is the dynamic load coefficient; Calculation of shear stress during dynamic load: Maximum shear stress under dynamic load t max =8aDP max / (πd 3 )≤[t]; Minimum shear stress under dynamic load t min =8aDP min / (πd 3 )≤[t]; Pulse fatigue limit stress calculation: t uo =0.32R m , where the tensile strength R m is a constant, depending on the spring steel material; Fatigue safety factor calculation: S = (t uo +0.75t min ) / t max ≥S min Among them, S min is the minimum safety factor.

6. The automatic design method for motorcycle springs according to claim 1, characterized in that: The spring stability check includes: locomotive spring height-to-diameter ratio λ=H0 / D≤3, wherein H0 is the free height of the spring.

7. A locomotive spring automatic design system for completing the locomotive spring automatic design method of claim 1, characterized in that: include: A locomotive spring data acquisition unit, used to acquire information on locomotive axle weight, number of locomotive axles, bogie weight, unsprung weight, primary spring static deflection, and secondary spring static deflection; A locomotive spring data calculation unit, used to calculate the load of each group of springs of the first series and the second series according to the data obtained by the locomotive spring data acquisition unit; The locomotive spring data selection unit is used to input feasible primary and secondary spring data, including spring center diameter D, spring wire diameter d, and working height H; The locomotive spring verification unit is used to perform verification calculations based on the numerical values ​​provided by the locomotive spring data selection unit, output the feasible value when the constraint conditions are met, and issue an alarm prompt when the constraint conditions are not met, and the prompt includes that the specific feasible data parameters are out of range.

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